Parameter identification of vector-controlled induction machines

Abstract

This paper describes the identification of electromagnetic time constants and stator resistance for field oriented induction motor drives. The model of an induction motor at standstill in terms of state representation is discussed. A direct continuous-time identification from the standstill time-domain test data is based on the parametrized observer state vector. In a laboratory configuration the stator resistance is influenced by the non-linear inverter gain function. Two categories of current responses to voltage steps and to pseudo random binary sequences are examined. The current transients indicate saturation effects. Parameter estimates of a linear machine model are determined using least squares algorithms. Simulation and experimental studies are carried out in a Matlab software environment. Corresponding results obtained for two induction motor drives of different power ratings are included.